PABLO FERRARI

Designed and built a self-sustaining SaaS using Claude Code as the primary development tool — live in production with paying subscribers, active development.

• Multi-tenant backend (Node.js + TypeScript + Express), accountant multi-business management, tiered subscription billing, audit log, and stock control
• Integrates Argentina's government invoicing API (ARCA/AFIP) for issuing invoice types A, B, C, E, and MercadoPago for recurring subscriptions
• In-app AI assistant for end users: context-aware prompts tailored to each business's invoicing history, plan, and AFIP status — powered by a multi-provider fallback chain (Claude → OpenAI → Gemini)
• AWS Lambda for PDF generation (Puppeteer), S3 for cert/doc storage with AES-256-GCM encryption, Cloudflare for delivery

• Integrated 10+ payment providers across North America, Europe, and APAC: Worldpay, Nuvei, NetworkMerchant, 2C2P (TH/PH), NicePay (KR), JusPay (IN), PayU, Klarna, Oxxo Pay, Authorize.net (eCheck), and Truemed HSA (US)
• Reversed a cascading approval rate decline using 3DS v2 via Worldpay — rates had fallen from 88% to ~50% month-over-month; recovered to 88% within weeks and stabilized at ~91%
• Integrated Google Pay and Apple Pay across multiple acquiring partners
• Improved approval rates by enriching transaction payloads (billing address, client IP, device signals) and implementing CIT/MIT flows for recurring subscriptions
• Co-designed and implemented a unified checkout platform consolidating all sales channels under a single payment layer, enabling new market rollouts without per-channel integration work

• Worked on the platform from 2019 to 2023 (Laravel web app, Cordova mobile app, Node.js service); the owner brought me back in 2026 to rebuild the entire product — backend, web, mobile app and infrastructure — as the sole developer
• Rebuilt the legacy PHP 7.1 / Laravel 5.7 + Cordova SaaS as a TypeScript monorepo (Express + Prisma API, Next.js web, React Native / Expo mobile), running in production in parallel with the legacy system so the cutover carries no risk for customers
• Reached full functional parity in ~5 weeks against a 3-month plan: 50 modules, 419 endpoints, 179 pages and 37/37 Excel reports — reusing proven legacy stored procedures instead of rewriting business logic
• Found and fixed silent legacy bugs, including a date-handling issue that under-reported lost workdays ~20× (741 vs 14,619) in accident severity metrics, plus broken stored procedures and a tenant-isolation gap
• Built AI-first observability (audit trail on every mutation, automatic incident capture with LLM root-cause analysis) and an AI onboarding pipeline that drafts a customer's risk matrix from spreadsheets — 83% accuracy on risk factor, validated on production data (15 clients, 92 sites)
• Set up CI/CD with GitHub Actions, GHCR and Docker on AWS EC2 with path-filtered deploys; migrated user files to S3

• Migrated legacy codebase from PHP 5.6 to PHP 8 + Laravel 9 with Blade templates, reducing landing page and checkout load times by ~50% while eliminating years of accumulated security debt
• Set up AWS CodePipeline + Elastic Beanstalk CI/CD for staging and production, replacing a fully manual deploy process
• Architected and shipped a real-time messaging MVP using AppSync + GraphQL + Next.js — owned end-to-end from blank file to production

• Built multi-property hotel KPI platform with automated data pipelines integrating M3 (PMS/accounting), Paychex (HR/payroll), and Google Places — pulling daily revenue, monthly budgets, and weekly forecasts across hotel groups
• Designed a rule-based bonus calculation engine with a CSS-specificity-like algorithm matching employees to formulas via configurable hierarchies, conditions, and priority weights

• Led migration of todosgamers.com from a PHP/Laravel monolith to ~10 Node.js/TypeScript microservices, maintaining the legacy system in parallel throughout
• High focus on logging and testing discipline; integrated Socket.io for real-time features, PayPal/Stripe APIs, and Vue.js frontend

• Designed the microservices architecture and led initial implementations for a French telecommunications operator — established technical patterns and tooling adopted by the broader team

• EdTech school management systems with BigBlueButton virtual classroom integration
• Security management platforms integrating Gmail, Google Maps, and AWS S3

• Built the CRM and public API layer for 100+ real estate agencies, synchronizing 50,000+ property listings daily across MercadoLibre, Zonaprop, Argenprop, OLX, and Properati